Encapsulation compositions and process for preparing the same

ABSTRACT

Encapsulation compositions in which an encapsulate (A) is encapsulated in a matrix (B) may be prepared by:  
     (i) mixing matrix (B) with a liquid plasticizer and encapsulate (A) in an extruder, to obtain a melted mixture of encapsulate (A) and matrix (B); and  
     (ii) extruding the melted mixture, to obtain an extruded mixture.

CROSS REFERENCES TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional PatentApplication No. 60/275,484, filed on Mar. 14, 2001, and which isincorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to encapsulation compositions inwhich an encapsulate is encapsulated in a glassy matrix. Moreparticularly, the present invention relates to flavor encapsulationcompositions in which a flavoring agent is encapsulated in a glassymatrix. The present invention further relates to processes for preparingsuch compositions.

[0004] 2. Discussion of the Background

[0005] The encapsulation of encapsulates is an area of active research.In particular, the encapsulation of encapsulates such as medications,pesticides (including insecticides, nematocides, herbicides, fungicides,microbicides etc.) preservatives, vitamins and flavoring agents isdesired for a number of reasons. In the case of medications andpesticides, encapsulation may be desired to achieve the controlledrelease of the medication or pesticide. In the case of vitamins,encapsulation may be carried out to protect the vitamin fromair-oxidation and, thus, to extend shelf life of the vitamin. In thecase of the flavoring agent, the encapsulation may be carried out toplace the flavoring in an easily metered form which will release theagent at a controllable event, such as the addition of water.

[0006] It is generally known to skilled practitioners in the field offlavor encapsulation that the current practical commercial processesleading to stable, dry flavors are limited to spray drying and extrusionfixation. The former process requires emulsification or solubilizationof the flavor in an aqueous carrier containing the encapsulation solids,followed by rapid drying in a high temperature, high velocity gas streamand collection as a low density bulk solid.

[0007] While spray drying accounts for the majority of commerciallyencapsulated flavor materials, several limitations of the process areevident. Low molecular weight components of complex or natural flavormixtures generally exhibit high vapor pressures and are usually lost ordisproportionate during the process. The resultant flavor-carriers areporous and difficult to handle. In addition, deleterious chemicalreactions such as oxidation can result on surfaces exposed during andafter drying. The final product, a dry, free flowing powder, willrelease the encapsulant rapidly upon hydration whether rapid release isdesired or not.

[0008] U.S. Pat. No. 3,971,852 discloses the use modified starch, gumsand other food polymers with low molecular weight polyhydroxy compoundswith spray drying to yield a glassy matrix with encapsulated oil at amaximum of 70-80% by volume. The system forms a shell surrounding theoil flavoring but is limited to lipophilic flavoring agents.

[0009] U.S. Pat. No 4,532,145, discloses a process for preparingcompositions in which a volatile flavorant is fixed by spray drying froma carrier solution made up of 10-30% of a low molecular weight componentsuch as a sugar or edible food acid with the balance of the solids beinga maltodextrin carbohydrate in the amount of 70-90%.

[0010] U.S. Pat. No. 5,124,162 discloses a carrier mixture composed ofmono- and disaccharides (22-45%), maltodextrins (25-50%), and a highmolecular weight carbohydrate such as chemically modified starch, gumarabic or gum acacia (10-35%) to which flavoring agents are added andthe subsequent solution spray dried to yield a free flowing powder witha bulk density of 0.50 g/cc.

[0011] U.S. Pat. No 5,601,760 discloses a carrier mixture utilizing wheyprotein isolates to encapsulate lipid flavor systems. The proteinconstitutes 35 to 100% of the encapsulating matrix with the remainderconsisting of sugars. Other disclosed proteins include whey proteinconcentrates, β-lactoglobulin and α-lactoalbumin.

[0012] Several technical issues unmet by these approaches are evident.First thermally sensitive flavors undergo undesirable reactionsincluding oxidations, rearrangements and hydrolyses. Secondly, volatilecomponents are lost or disproportionate during atomization andevaporation in the dryer.

[0013] A second process route, that of melt encapsulation has beenutilized to advantage with lipid-based flavors. In this technology, amelt is prepared by boiling off sufficient water from a high solidscarbohydrate syrup, adding flavoring oils with emulsifier, agitatingunder pressure to emulsify the oil in the melt and injecting the mixtureinto a chilling, dehydrating solvent bath to obtain fine rod-likefilaments. After solvent removal, the matrix is reduced in size and, insome cases, coated with an anti-caking agent before being packed. See,e.g., U.S. Pat. Nos. 2,809,895; 3,041,018; 2,856,291; 2,857,821; and3,704,137. Subsequent improvements in the art are disclosed in U.S. Pat.No. 3,314,803, for the encapsulation of volatiles such as acetaldehyde,and in U.S. Pat. No. 4,707,367, which discloses encapsulation of up to35% by weight flavor oil in the glassy matrix.

[0014] U.S. Pat. No 4,689,235 discloses the use of modifiedstarch-maltodextrin carriers in the range of 5 parts modified starch:95parts maltodextrin to 95 parts modified starch:5 parts maltodextrin. Thecarrier is dissolved to form a syrup, the water is cooked off, flavor isadded and emulsified, and the melt is injected into a solvent bath.

[0015] An alternative route to encapsulating flavors is disclosed inU.S. Pat. No. 4,230,687. In this approach, high molecular weightcarriers such as proteins, starches and gums are plasticized by additionof significant amounts of water in the presence of the encapsulate andsubjected to a high shear dispersing process. The rubbery or plasticmatrix with encapsulate is then extruded, recovered and dried to yield astable product.

[0016] Another alternative process, melt extrusion, can be utilized forflavor fixation and encapsulation. In this process, a melting system,i.e. an extruder, is employed to form the carrier melt in a continuousprocess. The encapsulated flavor is either admixed or injected into themolten carbohydrate carrier. U.S. Pat. No. 4,420,534 discloses the useof a matrix composition consisting of 10-30% of a low molecular weightcomponent chosen from a series of mono- and disaccharides, corn syrupsolids, or organic acid with a balance of the mixture beingmaltodextrin. The matrix is dry blended with an anhydrous liquidflavoring component and melted in a single screw extruder to yield asolid matrix characterized as a glass with a glass transitiontemperature greater than 40° C.

[0017] U.S. Pat. No. 5,972,395 discloses use of a matrix composed of 15to 40% of a high molecular weight carrier, preferably a maltodextrin andat least 40% of a low molecular weight carbohydrate, sugar polyol oradipic acid. The matrix is extruded to yield a solid matrixcharacterized as a glass.

[0018] U.S. Pat. Nos. 5,087,461 and 5,009,900 disclose a similarapproach utilizing a composition consisting of a modified food starch,maltodextrin, polyol and mono- and disaccharide components. The starchis a chemically modified water-soluble starch and is used in the amountof 40 to 80% of the total mixture. The balance of the composition iscomprised of 10 to 40% maltodextrin, 5 to 20% corn syrup solids orpolydextrose and 5 to 20% mono- or disaccharide. This matrix is made tobalance processing response with glass matrix character.

[0019] U.S. Pat. Nos. 6,187,351, 5,603,971, and 5,987,897 disclose theuse of a series of matrix compositions utilizing modified starch withmono- or disaccharides, modified starch with polyol, and food polymerplus carbohydrates. The use of water to plasticize the matrix in theextrusion process yields an encapsulated flavor matrix characterized byglass transition temperatures greater than 40° C. In U.S. Pat. No.6,187,351, the use of 2 to 45% of a food polymer, 25 to 80% of amaltodextrin, and 10 to 30% of a mono- or disaccharide or 24 D.E. to 42D.E. corn syrup solids is disclosed. The matrix is dry blended, fed intothe extruder with the required water plasticizer and flavor, and theresulting encapsulate is obtained as a glassy solid exhibiting a glasstransition temperature greater than 40° C. The disclosed polymersinclude modified celluloses, high methoxy pectin, gum arabic (acacia),locust bean gum, guar gum, and lesser gums such as gum ghatti, gumtragacanth and gum karaya. Also disclosed are proteins such as gelatinand α-casein, microbial gums such as xanthan and gellan, pregelatinizedstarches in addition to other carbohydrate polymers such as inulins,β-glucans and konjac flour.

[0020] U.S. Pat. No. 5,756,136 discloses the encapsulation of cinnamicaldehyde in a matrix containing at least 25% of a whey protein isolate.The resulting encapsulate exhibits a control release functionality andprotection for yeast-leavened dough.

SUMMARY OF THE INVENTION

[0021] In a number of the cited patents teaching melt extrusion, matrixcompositions were carefully defined to accommodate processinglimitations of the extruder as well as to generate a stable matrix beingin the glassy state and characterized by a glass transition temperatureof greater than 40° C.

[0022] Formation of a matrix in the glassy state is of particular valuefor encapsulation of water-soluble flavorings and extracts. The role ofwater as a plasticizing agent conflicts with the desired results,because water has the effect of lowering the glass transitiontemperature (Tg) of the glassy matrix. In model studies of a number offood carbohydrate systems, the upper limit of water content isapproximately 7-10 wt. % for lower molecular weight components such asmono- and disaccharides, maltodextrins and combinations of these agents.At higher water contents, the Tg is lowered to the extent that thematrix is in the undesirable rubbery, plastic or fluid state at roomtemperatures.

[0023] In order to insure higher Tg's there are several optionsavailable. By limiting the class of encapsulate materials to lipophilicmaterials such as citrus oils, plasticizing moisture can be removed by aboil off process as described in U.S. Pat. Nos. 2,856,291; 2,857,821;2,809,895; 3,041,018; 3,314,803; 3,704,137; and 4,707,367.Alternatively, the use of melt encapsulation disclosed in U.S. Pat. No.4,420,534 limits the flavoring agents to materials with lower vaporpressure which can be admixed to the premelt composition. In addition,flavorings which are in the form of aqueous extracts, water andalcohol-water solutions will result in a product with a Tg much below25° C. leading to plastic flow and loss of volatiles upon storage.

[0024] Similarly, in U.S. Pat. Nos. 5,009,900 and 5,972,395, theflavorings are limited to those with limited volatility and totalmoisture level in the product is less than 11% by weight. Many of thekey topnotes and unique flavor components of complex flavors have highvapor pressures at room temperature and are not easily encapsulated bysuch a process.

[0025] Matrix improvements for the continuous melt extrusion process aredescribed in U.S. Pat. Nos. 6,187,351, 5,603,971 and 5,987,897. The useof modified starch and food polymers with low molecular weightcarbohydrate plasticizers is detailed to yield encapsulates in a glassymatrix with greater than 40° C. However with these matrices the flavorloads are generally limited to 10 wt. % or less.

[0026] Preparation of a solid in the glassy state is dependent upon bothmatrix composition and the process used to generate the encapsulatingmaterial. The advantage of retaining the glass form of the matrix isincreased physical stability of the solid, reduced loss of incorporatedvolatiles, and reduction of deleterious intermolecular reactions andoxidation. A detailed discussion of the physical chemistry of water-foodpolymer interactions relating to the glassy state can be found in H.Levine and L. Slade, “Glass Transitions in Foods,” in Physical Chemistryof Foods, H. Schwartzberg and R. Hartel, Eds., Marciel Dekker, New York,pp. 83-205, 1992; and in H. Levine and L. Slade, “Water as aPlasticizer: physico-chemical aspects of low-moisture polymericsystems,” in Water Science Reviews, vol. 3, F. Franks, Ed. CambridgeUniversity Press, London, pp. 79-185, 1988, which are incorporatedherein by reference. The role of water as a plasticizer with foodpolymers, as well as the relationships between molecular compositionsand dynamics of interactions between various components, are discussedin these references.

[0027] Thus, there remains a need for encapsulation compositions inwhich an encapsulate is encapsulated in a matrix which is stable in theglass state at ambient temperatures. In particular, there remains a needfor flavor encapsulation compositions in which the flavoring agent isencapsulated in a matrix which is stable in the glassy state at roomtemperature, i.e. has a Tg sufficiently high to prevent caking andplastic flow at ambient room temperatures. There also remains a need fora flavor encapsulation compositions which exhibit increased flavor loadswith minimal surface oil levels. There also remains a need for flavorencapsulation compositions which have a high Tg and are amenable forencapsulating volatile and sensitive flavor components. There alsoremains a need for processes for preparing such compositions.

[0028] Accordingly, it is one object of the present invention to providenovel encapsulation compositions.

[0029] It is another object of the present invention to provide novelencapsulation compositions in which an encapsulate is encapsulated in amatrix which is stable in the glassy state at ambient temperatures.

[0030] It is another object of the present invention to provide novelflavor encapsulation compositions in which a flavoring agent isencapsulated in a matrix that is stable in the glassy state at ambienttemperatures.

[0031] It is another object of the present invention to provide novelflavor encapsulation compositions which are amenable to theencapsulation of volatile or sensitive flavor components.

[0032] It is another object of the present invention to provide novelflavor encapsulation compositions which exhibit increased loads offlavor oils.

[0033] It is another object of the present invention to provide novelflavor encapsulation compositions which exhibit low surface oil levels.

[0034] These and other objects, which will become apparent during thefollowing detailed description, have been achieved by the inventors'discovery that it is possible to prepare food polymer based glassymatrices, which have sufficiently high Tg to prevent plastic flow andcaking at ambient temperatures, by interacting one or more food polymerswith an aqueous plasticizer in the melting zone of an extruder andextruding the resulting mixture.

[0035] The inventors have also discovered that a composition comprising:

[0036] (A) an encapsulate, encapsulated in:

[0037] (B) a glassy matrix, said matrix comprising:

[0038] (a) 50 to 100% by weight, based on the total weight of saidmatrix (B), of gum arabic and 0 to 50% by weight, based on the totalweight of said matrix (B), of a low molecular weight carbohydrate orpolyol; or

[0039] (b) 50 to 100% by weight, based on the total weight of saidmatrix (B), of hydrolyzed gelatin and 0 to 50% by weight, based on thetotal weight of said matrix (B), of a low molecular weight carbohydrateor polyol; or

[0040] (c) 50 to 90% by weight, based on the total weight of said matrix(B), of a 50 to 75 Bloom gelatin and 10 to 50% by weight, based on thetotal weight of said matrix (B), of a low molecular weight carbohydrateor polyol; or

[0041] (d) 50 to 100% by weight, based on the total weight of saidmatrix (B), of larch gum and 0 to 50% by weight, based on the totalweight of said matrix (B), of a low molecular weight carbohydrate orpolyol; or

[0042] (e) 50 to 100% by weight, based on the total weight of saidmatrix (B), of a mixture of at least two food polymers selected from thegroup consisting of gum arabic, hydrolyzed gelatin, gelatin, and larchgum and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol,

[0043] are stable in the glassy state, i.e., have a sufficiently high Tgto prevent plastic flow and caking at ambient temperature.

[0044] The inventor have also discovered that the present encapsulationcompositions may be prepared by a process comprising:

[0045] (i) mixing matrix (B) with a liquid plasticizer and encapsulate(A) in an extruder, to obtain a melted mixture comprising encapsulate(A) and matrix (B); and

[0046] (ii) extruding said melted mixture.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0047] As noted above, the present invention has been made possible inpart, by the inventors' discovery that it is possible to prepare foodpolymer-based matrices which contain at least 50% by weight, based onthe weight of the matrix ingredients, of food polymer in the matrixcomposition, which have sufficiently high Tg such that the glassy matrixis stable at ambient temperatures, with the use of aqueous plasticizer.Thus the inventors have discovered that with the use of aqueousplasticizer it is possible to prepare a matrix containing over 50% byweight of a food polymer which does not undergo plastic flow or cakingat ambient temperatures. This discovery is a surprising resultconsidering the well-known large glass-transition-lowering effect ofwater in carbohydrate and protein based systems. Accordingly, before thepresent invention, one skilled in the art would not have expected that astable glassy carbohydrate- or protein-based food polymer could havebeen practically prepared using an aqueous plasticizer.

[0048] Thus, in a first embodiment, the present invention providesactive agent encapsulation compositions in which (A) an encapsulate isencapsulated in (B) a glassy matrix comprising:

[0049] (a) 50 to 100% by weight, based on the total weight of saidmatrix (B), of gum arabic and 0 to 50% by weight, based on the totalweight of (a), of a low molecular weight carbohydrate or polyol; or

[0050] (b) 50 to 100% by weight, based on the total weight of saidmatrix (B), of hydrolyzed gelatin and 0 to 50% by weight, based on thetotal weight of said matrix (B), of a low molecular weight carbohydrateor polyol; or

[0051] (c) 50 to 90% by weight, based on the total weight of said matrix(B), of a 50 to 75 Bloom gelatin and 10 to 50% by weight, based on thetotal weight of said matrix (B), of a low molecular weight carbohydrateor polyol; or

[0052] (d) 50 to 100% by weight, based on the total weight of saidmatrix (B), of larch gum and 0 to 50% by weight, based on the totalweight of said matrix (B), of a low molecular weight carbohydrate orpolyol; or

[0053] (e) 50 to 100% by weight, based on the total weight of saidmatrix (B), of a mixture of at least two food polymers selected from thegroup consisting of gum arabic, hydrolyzed gelatin, gelatin, and larchgum and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol.

[0054] The term encapsulate as used in the present invention, includesagents such as medications, pesticides, preservatives, vitamins, foodacids, salts, flavoring agents, perfumery chemicals and fragrances, andfood colorants both synthetic and natural. Suitable medications includeantacids, anti-inflammatory substances, coronary vasodilators, cerebralvasodilators, peripheral vasodilators, anti-infectives, psychotropics,anti-manics, stimulants, antihistamines, laxative, decongestants,vitamins, gastrointestinal sedatives, antidiarrheal preparations,antianginal drugs, antiarrhythmics, antihypertensive drugs,vasoconstrictors, migraines treatments, anticoagulants, antithromboticdrugs, analgesics, antipyretics, hypnotics, sedatives, antiemetics,antinauseants, anticonvulsants, thyroid and antithyroid preparations,diuretics, antispasmodics, uterine relaxants, mineral and nutritionaladditives, antiobesity drugs, anabolic drugs, erythropoietic drugs,antiasthmatics, expectorants, cough suppressants, mucolytics,antiuricemic drugs and other drug substances such as topical analgesics,local anesthetics and the like.

[0055] Suitable pesticides include insecticides, nematocides,fungicides, herbicides, and microbicides. Insecticides, which may beencapsulated in the present compositions include those disclosed inKirk-Othmer, Encyclopedia of Chemical Technology, 4^(th) Ed., vol. 14,Wiley, New York, pp. 524-602, 1995, and 3^(rd) Ed., vol. 13, pp.313-485,1981, both of which are incorporated herein by reference. Suitablenematocides include, e.g., methylN′N′-dimethyl-N-[(methylcarbamox)oxy]-1-thiooxamimidate (oxamyl) andthose disclosed in Kirk-Othmer, Encyclopedia of Chemical Technology,4^(th) Ed., vol. 24, Wiley, New York, pp. 830-831, 1997, and 3^(rd) Ed.,vol. 18, pp.305-308 (1982), both of which are incorporated herein byreference. Suitable fingicides include those disclosed in Kirk-Othmer,Encyclopedia of Chemical Technology, 4^(th) Ed., vol. 12, Wiley, NewYork, pp. 204-227, 1994, and 3^(rd) Ed., vol. 11, pp. 490-498, 1980,both of which are incorporated herein by reference. Suitable herbicidesinclude those disclosed in Kirk-Othmer, Encyclopedia of ChemicalTechnology, 4^(th) Ed., vol. 13, Wiley, New York, pp. 73-136, 1995, and3^(rd) Ed., vol. 12, pp. 297-351, 1980, both of which are incorporatedherein by reference. Suitable antibiotics and antimicrobials includethose disclosed in Kirk-Othmer, Encyclopedia of Chemical Technology,4^(th) Ed., vol. 2, Wiley, New York, pp. 854-1018 (1992), and vol. 3,pp. 1-346 (1992), both of which are incorporated herein by reference.Suitable vitamins include those disclosed in Kirk-Othmer, Encyclopediaof Chemical Technology, 4^(th) Ed., vol. 25, Wiley, New York, pp. 1-17,1998, and 3^(rd) Ed., vol. 24, pp. 1-277, 1984, both of which areincorporated herein by reference. Suitable food additives, in additionto flavoring agents, include those disclosed in Kirk-Othmer,Encyclopedia of Chemical Technology, 4^(th) Ed., vol. 11, Wiley, NewYork, pp. 805-833, 1994, and 3^(rd) Ed., vol. 11, pp. 146-163, 1980,both of which are incorporated herein by reference.

[0056] The term flavoring agent includes spice oleoresins and oilsderived from allspice, basil, capsicum, cinnamon, cloves, cumin, dill,garlic, marjoram, nutmeg, paprika, black pepper, rosemary and turmeric;essential oils: anise oil, caraway oil, clove oil, eucalyptus oil,fennel oil, garlic oil, ginger oil, peppermint oil, onion oil, pepperoil, rosemary oil, and spearmint oil; citrus oils such as orange oil,lemon oil, bitter orange oil and tangerine oil; alliaceous flavors:garlic, leek, chive, and onion; botanical extracts: arnica flowerextract, chamomile flower extract, hops extract, and marigold extract;botanical flavor extracts: blackberry, chicory root, cocoa, coffee,kola, licorice root, rose hips, sassaparilla root, sassafras bark,tamarind and vanilla extracts; protein hydrolysates: hydrolyzedvegetable protein (HVP'S), meat protein hydrolysates, milk proteinhydrolysates; and compounded flavors both natural and artificialincluding those disclosed in S. Heath, Source Book of Flavors, AviPublishing Co. Westport, Conn., pp. 149-277, 1981, which is incorporatedherein by reference. Representative flavor compounds are for example:benzaldehyde, diacetyl (2,2-butanedione), vanillin, ethyl vanillin andcitral (3,7-dimethyl-2,6-octadienal). The flavoring agent may be in theform of an oil, aqueous solution, non-aqueous solution or an emulsion.Flavor essences, i.e. the water-soluble fraction derived from fruit orcitrus can be utilized although at lower levels than the ingredientsreferenced above. As will be described more fully below, the presentinvention is particularly advantageous when the flavoring agent isitself a volatile compounds with varying vapor pressures at ambientconditions

[0057] When the encapsulate is lipophilic, the encapsulate is dispersedin the glassy matrix of the final product usually with the aid of anemulsifier added to the lipophilic phase or in the matrix mixture.

[0058] Although the exact amount of encapsulate encapsulated in thematrix will depend, in part, upon the precise nature of the matrix, andthe anticipated end use of final composition, the encapsulationcompositions of the present invention will typically comprise 4 to 18%by weight, based on the total weight of the composition, of encapsulate.Preferably, the present encapsulation compositions will comprise 9 to16% by weight, based on the total weight of the composition, ofencapsulate. It is preferred that the encapsulate is a flavoring agent.

[0059] In addition to the foregoing encapsulates, various optionalingredients such as conventionally used in the art, may be included inthe compositions of the present invention. For example, colorings,sweeteners, food acids, salts, fragrances, diluents, fillers,preservatives, anti-oxidants, stabilizers, lubricants, and the like maybe employed herein if desired.

[0060] As noted above, the encapsulate is encapsulated in a glassymatrix of one of (a), (b), (c), (d), or (e). In all the followingdescriptions of the matrices (a), (b), (c), (d), and (e) all % by weightvalues are based upon the total weight of matrix (B).

[0061] In the following descriptions, the term food polymer will be usedto characterize the major component of the encapsulating matrix. Thefood polymers herein referred to are specifically gelatin, gum arabic,larch gum arabinogalactan and hydrolyzed gelatin. Modified starch,specifically n-octenylsuccinate modified starch, may also be consideredto be a food polymer but is not considered as such for the purposes ofthe present invention. The various forms of carbohydrate materials rangefrom high molecular weight starches through the hydrolysis oligomers,the maltodextrins, to the lower molecular weight corn syrup solids andultimately mono- and disaccharides. The maltodextrins may be consideredas food polymers, however, they are not used in that context in thepresent invention.

[0062] In one embodiment, the glass matrix comprises (a) 50 to 100% byweight, based on the total weight of the matrix (B), of gum arabic and 0to 50% by weight, based on the total weight of the matrix (B), of a lowmolecular weight carbohydrate or polyol. Preferably in embodiment (a),the glass matrix comprises (a) 50 to 99% by weight, based on the totalweight of the matrix (B), of gum arabic and 1 to 50% by weight, based onthe total weight of the matrix (B), of a low molecular weightcarbohydrate or polyol. Even more preferably, the glass matrix comprises60 to 80% by weight, based on the total weight of the matrix (B), of thegum arabic and 20 to 40% by weight, based on the total weight of thematrix (B), of a mono- or disaccharide.

[0063] Gum arabic is an exudate gum obtained from Acacia trees. The mainspecies are Acacia senegal and Acacia seyal. Gum arabic is a branchedmolecule with a main chain of (1→3)-linked β-D-galactopyranosyl unitshaving side chains, consisting of (1→3)-linked β-D-galactopyranosylunits, joined to it by (1→6)-linkages. The resulting side chains consistof various acidic sugars (see Industrial Gums, R. Whistler and J.BeMiller, Eds., 3^(rd) Edition, Academic Press, pp. 311-318, 1993). Thehydrocolloid shows enhanced solubility and relatively low viscosities insolutions of 30 to 40 wt. % solids.

[0064] Generally the A. Senegal gum is used to make beverage emulsions,while the A. seyal gum is used for spray drying applications. In spraydrying, the key functional characteristics of the polymer are itsemulsifying capacity, good film-forming properties upon drying andreasonably low aqueous viscosity. One key commercial specification forthe A. seyal is the degree of color contributed by the gum. With somedarker lots of the gum, a bleaching step is sometimes added to lightenthe product color by oxidation. Unexpectedly it was discovered by thepresent inventors that only unbleached A. seyal or A. senegal can beextruded in a manner which protects the freshly exited molten extrudatefrom flashing off flavor volatiles.

[0065] The selected gum arabic constitutes 50 to 100% by weight of thematrix (B). The remainder of the matrix is low molecular weight foodcarbohydrates and/or polyols. Suitable carbohydrates are mono- anddisaccharides, invert syrups, molasses, corn syrups, and 36 to 42 D.E.corn syrup solids. Suitable polyols are erythritol, sorbitol, mannitol,lactitol, maltitol, isomalt (Palatinit®), dulcitol, xylitol,hydrogenated corn syrups, hydrogenated glucose syrups, hydrogenatedmaltose syrups, and hydrogenated lactose syrups. The preferredcarbohydrates are glucose and maltose, and the preferred polyols aremannitol, sorbitol, and isomalt.

[0066] In another embodiment, the glass matrix comprises (b) 50 to 100%by weight, based on the total weight of said matrix (B), of hydrolyzedgelatin and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol. Preferably inembodiment (b), the glass matrix comprises 50 to 99% by weight, based onthe total weight of said matrix (B), of hydrolyzed gelatin and 1 to 50%by weight, based on the total weight of said matrix (B), of a lowmolecular weight carbohydrate or polyol. Even more preferably inembodiment (b), the glass matrix comprises 60 to 80% by weight, based onthe total weight of the matrix (B), of the hydrolyzed gelatin and 20 to40% by weight, based on the total weight of the matrix (B), of a polyolor a mono- or disaccharide.

[0067] In another embodiment, the glass matrix comprises (c) 50 to 90%by weight, based on the total weight of said matrix (B), of 50 to 75Bloom gelatin and 10 to 50% by weight, based on the total weight of saidmatrix (B), of a low molecular weight carbohydrate or polyol. Preferablyin embodiment (c), the glass matrix comprises 60 to 80% by weight, basedon the total weight of the matrix (B), of the 50 to 75 Bloom gelatin and20 to 40% by weight, based on the total weight of the matrix (B), of apolyol or a mono- or disaccharide.

[0068] Gelatin, the soluble protein extract from collagen, comes fromvarious animal sources and in different forms. There are acid-extractedand base-extracted forms of gelatin. The key difference of the two formsbeing in the isoelectric point of the resultant, soluble polymer.Sources of the collagen used for extraction to generate the gelatininclude cattle hides and pork skins. The type and degree of extractionlead to various grades of gelatin. Acid hydrolysis of the collagen leadsto Type A acid gelatin. Similarly base hydrolysis and extraction leadsto a Type B gelatin. The isoelectric points are generally in the pHrange of 7 to 9 for Type A; and 4.7 to 5.1, for Type B). Gelatins aregenerally characterized by their gelling strength in terms of Bloomusing a standardized procedure and a Bloom gelometer. Commercialgelatins vary from 50 to 300 Bloom with the high values indicatingstronger gels (see M. Glicksman, Gum Technology in the Food Industry,Academic Press, pp. 359-397, 1969). The particular gelatins which aremost compatible with the extrusion encapsulation process of the presentinvention are the 50 and 75 Bloom gelatins of both type A and B.

[0069] Another form of gelatin is the hydrolyzed gelatins. Theseproducts are derived from the standard gelatin by an additionalhydrolysis step. The result is a water soluble, non-gelling form of thefood protein. Generally molecular weights of the hydrolyzed gelatins arein the 100,000 dalton range. Hydrolyzed gelatins are the preferred formof the gelatin for the present encapsulation matrices.

[0070] In another embodiment, the glass matrix comprises (d) 50 to 100%by weight, based on the total weight of said matrix (B), of larch gumand 0 to 50% by weight, based on the total weight of said matrix (B), ofa low molecular weight carbohydrate or polyol. Preferably in embodiment(d), the glass matrix comprises 50 to 99% by weight, based on the totalweight of said matrix (B), of larch gum and 1 to 50% by weight, based onthe total weight of said matrix (B), of the low molecular weightcarbohydrate or polyol. Even more preferably in embodiment (d), theglass matrix comprises 60 to 80% by weight, based on the total weight ofthe matrix (B), of the larch gum and 20 to 40% by weight, based on thetotal weight of the matrix (B), of a mono- or disaccharide.

[0071] In matrix (d), the food polymer is larch gum or larcharabinogalactan. These hydrocolloids are obtained from extracts of larchwoods (see Industrial Gums, R. Whistler and J. BeMiller, Eds., 3^(rd)Edition, Academic Press, p. 304, 1993). The larch arabinoglalactanhydrocolloid polymer consists of two fractions: the smaller with amolecular weight of 16,000 to 18,000 daltons, constituting approximately80% of the mixture, and the remaining 20% with a molecular weight in therange of 80,000 to 100,000 daltons. One unique characteristic of larchgum is its very reduced solution viscosity at high total solids.

[0072] In another embodiment, the glass matrix comprises (e) 50 to 100%by weight, based on the total weight of said matrix (B), of a mixture ofat least two food polymers selected from the group consisting of gumarabic, hydrolyzed gelatin, gelatin, and larch gum and 0 to 50% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol. Preferably in embodiment (e), the glassmatrix comprises 50 to 99% by weight, based on the total weight of saidmatrix (B), of a mixture of at least two food polymers selected from thegroup consisting of gum arabic, hydrolyzed gelatin, gelatin, and larchgum and 1 to 50% by weight, based on the total weight of said matrix(B), of the low molecular weight carbohydrate or polyol. Even morepreferably in embodiment (e), the glass matrix comprises 60 to 80% byweight, based on the total weight of the matrix (B), of the a mixture ofat least two food polymers selected from the group consisting of gumarabic, hydrolyzed gelatin, gelatin, and larch gum and 20 to 40% byweight, based on the total weight of the matrix (B), of a mono- ordisaccharide.

[0073] In embodiments (b), (c), (d), and (e), the low molecular weightcarbohydrates and polyols are the same as those described above formatrix (a).

[0074] In another embodiment, the present invention provides a processfor preparing the present encapsulation compositions, which comprises:

[0075] (i) mixing matrix (B) with a liquid plasticizer and encapsulate(A) in an extruder, to obtain a melted mixture comprising encapsulate(A)and matrix (B); and

[0076] (ii) extruding said melted mixture.

[0077] In the present process, the liquid plasticizer may be any whichis suitable for facilitating the formation of the melt in the extruderwhile at the same time affording a product which exists in the glassystate, rather than the plastic or rubbery state at room temperature.Suitable plasticizers include water; glycerol; propylene glycol; aqueoussolutions of glycerol, propylene glycol, monosaccharides, anddisaccharides; and invert and high fructose corn syrups. When theencapsulate is a flavor and the final product is intended to be used asa food additive, the plasticizer should be a food grade solvent. In onepreferred embodiment, the present compositions are prepared by utilizingwater as the liquid plasticizer.

[0078] The plasticizer is added in an amount which results in theformation of a melt in the extruder, while at the same time affording aproduct which exists in the glassy state at room temperature. Thus, theamount of the plasticizer added may be selected to afford a productwhich has a Tg of at least 30° C., preferably at least 35° C., morepreferably at least 40° C.

[0079] The matrix (B), along with the plasticizer forms a melt in theextruder. Although the mixing action of the extruder will supply heat tothe matrix/plasticizer mixture, it will typically be necessary to supplyadditional heat to ensure formation of the melt. The encapsulate (A) iscontinuously added in a liquid phase to the feeding zone of the extruderby injection and mixed with the melted matrix/plasticizer mixture beforeexiting the extruder. In some embodiments, it may be preferred to add anon-aqueous, liquid plasticizer may be added to the encapsulate phase.

[0080] In certain embodiments, a surface-active agent, i.e. anemulsifier can be added to the dry blend, or preferably added to theliquid flavor mix which is ultimately injected into the metering zone ofthe extruder. These emulsifiers can be from the class of distilledmonoglycerides, mono- and diglyceride blends, propyleneglycolmonoglycerides, lecithin, modified lecithins, acetylated monoglycerides,lactylated monoglycerides, lactylated propyleneglycol monoglycerides,sorbitan esters, sorbitan-polyoxyethylene [20] monoglycerides,polyglycerol esters, DATEM's (diacetyltartarate esters ofmonoglycerides), succinylated esters of monoglycerides andpolyoxyethylenepropylene copolymers and mixtures thereof. Most preferredsurfactants are the sorbitan-polyoxyethylene [20] monoglycerides,lecithins, and polyglycerol esters.

[0081] The flavorants can be compounded flavors, essential oils, citrusoils, fruit extracts and essences, oleoresins and other forms. In somecases, the flavors can be diluted in a series of flavor solvents. Theseinclude fractionated coconut oils (medium chain triglycerides),propyleneglycol, glycerol, triacetin (glycerol triacetate) among others.

[0082] In a preferred embodiment, the use of a twin screw extruder ispreferred.

[0083] When the encapsulation composition exits the extruder, it may becooled by remaining in ambient temperature air, or in chilled orsubambient temperature air, or by passing through a liquid bath, with orwithout temperature control. Although not necessary, the cooled productmay be further processed by size reduction, for example by grinding orpulverizing. The product may also be treated with a anti-agglomerationcompound either before or after size reduction.

[0084] One key physical property of the flavor-containing glassyextrudate is the level of surface oil. These levels will be a functionof melt process, matrix composition and die geometry. By using a finedie orifice, the resulting thin strands of extrudate will have highersurface areas and by inference increasing levels of surface oil. Aseries of compositions were tested for surface oil by washing the samplesurface with hexane, filtering of suspended particles and reading theoptical density of the solution at a chosen wavelength (usually 230 nmin the U.V.). The reading is then compared to a set of dilutionstandards of the same flavor in hexane. By using the correspondingcorrection factors, a surface oil value in grams of flavor per 100 gramsof sample can be determined. The values obtained ranged from 0.0001grams of surface oil/100 grams of sample in the best case example (forthe hydrolyzed gelatin-mannitol compositions) to 0.13 grams of surfaceoil/100 grams of sample with gum arabic-maltose-dextrose carriers. Theextremely low levels of surface oil are unexpected and allow acommercial product to be prepared without additional steps of solventwashing and desolventizing the product.

[0085] It was determined experimentally by the present inventors thatonly a limited number of food polymers were functional in the meltextrusion process, restricting the exiting melt from “flashing off”volatiles, to generate a glassy matrix and exhibit good flavorencapsulation capabilities. It is now a general conjecture by thepresent inventors that low solution viscosity of a limited number offood polymers can be used to correlate with desired melt viscosities inthe extruder. It is most likely that there is a correlation between bothviscosities and the average molecular weight of polymers or compactstructures of polymer molecules or both. In other words, the lower themolecular weight of a polymer and the more compact structure of thepolymer, the lower will be the viscosity of its solution or melt. Inaddition to viscosity, a lower molecular weight of the polymer willreduce elastic recovery of the material at the die exit and favor shortsetting times of the material thus reducing loss of volatileencapsulate.

[0086] As noted above, there are a limited number of polymers and foodpolymer oligomers used with the low moisture environments of the ‘syrup’melt extrusion and continuous melt extrusion processes. In both of theformer processes, use of a specific, chemically-modified food starch hasplayed a dominant role. This material which is the n-octenylsuccinatederivative of dextrinized starch, is sold under the trade names ofCapsul (National Starch Company) and Amiogum (Cerestar). The productcould be more correctly characterized as a modified dextrin since thedextrinization process leads to average molecular weights of 30,000 to50,000 for the carbohydrate polymer. The material advantages ofexcellent solubility and low solution viscosities found in the ranges of35 to 45% dissolved solids must be balanced against the negativeattributes such as the acidic character derived from the bound succinicacid groups (solution pH values in the range of 2.5-3.0) and thedistinctive “cardboardy” after-taste which is results from the roastingor dextrinization step in processing the starch.

[0087] To test the hypothesis that low solution viscosity at highdissolved solids of selected food polymers can relate directly topractical extrusion melt viscosities, a series of food polymer solutionswere prepared at 40% w/w total solids and 50% w/w total solids, heatedto insure hydration, and equilibrated overnight. A BrookfieldViscometer, Model RVDV II was employed utilizing a spindle RV2. Readingswere taken at a number of speeds. The results are given in Table I.TABLE I Comparative Solution Viscosities of Selected Food Polymers Usinga Brookfield Model RV DV II Viscometer with Spindle RV2 Viscosity (cps)Food Polymer 40% Total Solids 50% Total Solids Capsul¹ 137 163Hydrolyzed  74 144 Gelatin² Gum Arabic³ 440 3500  Larch Gum⁴  48 107

[0088] From the solubility-viscosity relationsips for the abovepolymers, it could be predicted that any additional food polymers withsimilar solution solubility-viscosity responses might be predicted toform glassy extrudate according to these current teachings.

[0089] Moreover it is known in the polymer and plastics industry thatpolymer melts can be co-soluble, or alternately, separate incompatiblephases during melt extrusion. In aqueous concentrated solutions,thermodynamic incompatibility or limited co-solubility of biopolymers isa well-known phenomenon affecting structure and key functionalproperties of their solutions. For an aqueous solution of a pair ofwater-soluble biopolymers the region of co-solubility, corresponding toa relatively low concentration of both polymers, would be asingle-phase, transparent solution. Above this concentration, the systemwill form two layers (phases) with a predominant concentration of one ofthe biopolymers in one of the phases. Extensive mixing of the two-phasesolution would lead to a water-in-water type of emulsion. This simplescenario does not assume formation of any soluble or insoluble complexesbetween biopolymers when structure of the solution will be more complex.Numerous publications describe behavior of biopolymers in solutions andgels, however data is limited or non-existent for compatibility of foodbiopolymers in a melt. The major issue is in the high temperatures(above water boiling point) usually needed to form a biopolymer melt atlow water content and high melt viscosity preventing equilibriumseparation of phases.

[0090] A multiphase structure of composite biopolymer melts based on soyprotein and maltodextrin has been observed with optical microscopy, SEM,X-ray and near-IR spectroscopy (see Yuryev, V. P., Zasypkin, D. V.,Ghenin, Ya. V., Zhukov, V. A., Alexeyev, V. V. & Tolstoguzov, V. B.,“Role of maltodextrin in promoting structure formation in extruded soyaisolate,” Carbohydrate Polymers, vol. 15, pp. 243-253 (1991)).

[0091] Composite materials have been produced by thermoplasticextrusion, by using a cooling die to suppress melt expansion and changesin structure. It was inferred that the multiphase structure resultedfrom incompatibility or/and kinetics of mixing of biopolymers in themelt (see Zasypkin, D. V., Yuryev V. P., Alexeev, V. V. & Tolstoguzov,V. B., Carbohydrate Polymers, vol. 18, pp. 119-124 (1992)).

[0092] Limited co-solubility of biopolymers and multiphase structure ofthe blends can be expected to have a profound effect on flavorencapsulation in such mixed systems. In a general case, one polymerhaving a stronger affinity to a flavor and carrying most of it can beencapsulated in the continuous phase formed by the second polymer. Whilethe inventors acknowledge that the field of food polymer-polymer meltextrusion has not been adequately reported, it appears that co-meltingof mixed polymers with the addition the carbohydrate plasticizer can beachieved by the procedure described herein.

[0093] In the extrusion process, the matrix mixture contains lowermolecular weight components. For the gelatin and hydrolyzed gelatinsystems, polyols are preferred to avoid the Maillard browning reactionswhich result from the reaction of the side chain amino acids andreducing sugars. For the non-protein food polymers, the choice of lowmolecular weight carbohydrate is determined by the melt dynamics of theextruder. In certain cases, the monosaccharides and disaccharides can bein the form of crystalline hydrates. For glucose monohydrate the watercontribution is 10% by weight of the crystalline sugar. For maltose orlactose monohydrate, that contribution falls to 5 wt. % added water. Insuch cases the water stream added as a plasticizer for the melt will beadjusted to compensate for the internal free water contributed by the“melting” of the water of crystallization.

[0094] Other features of the invention will become apparent in thecourse of the following descriptions of exemplary embodiments which aregiven for illustration of the invention and are not intended to belimiting thereof.

EXAMPLES

[0095] Melt extrusion was accomplished utilizing a laboratory 2″co-rotating twin-screw extruder incorporating oil jacket heating, fittedwith a liquid injection port in the transfer zone of the unit, andutilizing a 0.031″ multi-orifice die. A matrix consisting of preblendedfood polymer(s) and carbohydrate were metered into the feed port at afeed rate between 100 to 130 grams/minute of solids; the water(plasticizer) liquid stream was delivered to the feed port by a meteringperistaltic pump at approximately 3-5 ml/minute The jacket temperaturewas set at 250° F. Two liquid flavors were prepared as concentrates: alipid-based flavor, “lemonade,” utilizing a lemon citrus oil base, and acompounded peach flavor. In some cases an emulsifier such as polysorbate60 (polyoxyethylene [20] sorbitan mono stearate) was added to the flavorat 0.5 to 5% (w/w emulsifier/flavor). In selected formulaspropyleneglycol was added as a separate liquid stream or as a cosolventwith the selected flavor. After lining out the feed and conveying ratesand bringing the unit into a steady-state, the extrudate was air cooledand collected in the form of fine strands which rapidly set into abrittle, glassy solid.

Example 1

[0096] A polymer matrix blend consisting of 80% by weight of hydrolyzedgelatin and 20% by weight of mannitol was prepared. The matrix was fedinto the extruder, water was added to the feed port at approximately 3to 5 ml/minute (˜2 to 4% by weight of the total feed rate), and a flavorstream consisting of lemonade flavor was metered into the extruder feedzone at a rate equivalent to a flavor load of 12% by weight. The productwas obtained as fine threads directly from the die which rapidly setinto a glassy solid. Analyses showed that the product had a flavor loadof 10.5% by weight, based on the total weight of the composition, and aTg of 50.1° C. as determined by DSC. The surface oil of the unmilledstrands was determined by a solvent wash. The product exhibited lessthan 0.0001% by weight, based on the total weight of the composition, ofsurface oil.

Example 2

[0097] A polymer matrix blend consisting of 80% by weight of hydrolyzedgelatin and 20% by weight of isomalt was prepared. The matrix was fedinto the extruder, water was added to 3 to 5 ml/minute to the feed zone,and a flavor stream consisting of lemonade flavor was metered into theextruder melt zone at a flavor load level of 16% by weight. The productstrains rapidly set into a glassy solid. Analyses showed the product hada flavor load of 14.6% by weight, based on the total weight of thecomposition, and a Tg of 55.7° C. The material exhibited <0.001% byweight, based on the total weight of the composition, of surface oil.

Example 3

[0098] A polymer matrix consisting of 100% by weight of hydrolyzedgelatin was utilized. A lemonade flavor was added at a feed rate equalto 16% by weight and the mixture was melted and obtained as a glassysolid. The flavor load analyzed by VOSD showed that the flavor load was14.1% by weight, based on the total weight of the composition, and theTg was 36.9° C. Surface oil was found to be <0.02% by weight, based onthe total weight of the composition.

Example 4

[0099] A polymer matrix blend of 60% by weight of gum arabic, 25% byweight of maltose monohydrate, and 15% by weight of anhydrous dextrosewas utilized and fed into the extruder. A lemonade flavor was added atan estimated level of 9% by weight. Analysis by VOSD showed the glassyencapsulation matrix had a flavor load of 6.3% by weight, based on thetotal weight of the composition, and a Tg of 39.5° C. by DSC analysis.The surface oil was found to be 0.13% by weight, based on the totalweight of the composition.

Example 5

[0100] A polymer matrix consisting of 55% by weight of gum arabic, 25%by weight of hydrolyzed gelatin, and 20% by weight of mannitol was addedto the extruder. A peach flavor containing propyleneglycol as aplasticizing agent and polysorbate 60 emulsifier was metered in at anestimated level of 10% by weight. A solid, glassy encapsulate wasobtained. Upon analysis the material showed a Tg of 44.1° C. and aflavor load by GLC analyses of 9.3% by weight, based on the total weightof the composition (averaged over four of the key flavor components).

Example 6

[0101] A food polymer matrix consisting of 80% by weight of hydrolyzedgelatin and 20% by weight of mannitol was added to the extruder with aseparate water plasticizing stream. Peach flavor containingpropyleneglycol and polysorbate 60 emulsifier was added at an estimatedlevel of 18% by weight. The encapsulate was obtain as brittle threadsand showed a Tg of 39.1° C. The flavor level was determined by GLCanalyses to be 12% by weight, based on the total weight of thecomposition.

Example 7

[0102] A food polymer matrix consisting of 80% by weight of 75 Boomgelatin and 20% by weight of mannitol was added to the extruder alongwith a separate water plasticizing stream. A lemonade flavor containingpolysorbate 60 was metered into the melt zone of the extruder at anestimated level of 9% by weight. A solid was obtained with a glassycharacter having a Tg of 51.5° C. The flavor load was determined to be8.7% by weight, based on the total weight of the composition, and thesurface oil was 0.023% by weight, based on the total weight of thecomposition.

[0103] Obviously, numerous modifications and variations of the presentinvention are possible in light of the above teachings. It is thereforeto be understood that, within the scope of the appended claims, theinvention may be practiced otherwise than as specifically describedherein.

[0104] All patents and other references mentioned above are incorporatedin full herein by this reference, the same as if set forth at length.

1. An encapsulation composition, comprising: (A) an encapsulate,encapsulated in: (B) a glassy matrix, said matrix comprising: (a) 50 to100% by weight, based on the total weight of said matrix (B), of gumarabic and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol; or (b) 50 to 100%by weight, based on the total weight of said matrix (B), of hydrolyzedgelatin and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol; or (c) 50 to 90%by weight, based on the total weight of said matrix (B), of a 50-75Bloom gelatin and 10 to 50% by weight, based on the total weight of saidmatrix (B), of a low molecular weight carbohydrate or polyol; or (d) 50to 100% by weight, based on the total weight of said matrix (B), oflarch gum and 0 to 50% by weight, based on the total weight of saidmatrix (B), of a low molecular weight carbohydrate or polyol; or (e) 50to 100% by weight, based on the total weight of said matrix (B), of amixture of at least two food polymers selected from the group consistingof gum arabic, hydrolyzed gelatin, gelatin, and larch gum and 0 to 50%by weight, based on the total weight of said matrix (3), of a lowmolecular weight carbohydrate or polyol.
 2. The composition of claim 1,wherein said matrix (B) comprises: (a) 50 to 100% by weight, based onthe total weight of said matrix (B), of gum arabic and 0 to 50% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol.
 3. The composition of claim 2, whereinsaid matrix (B) comprises: (a) 50 to 99% by weight, based on the totalweight of said matrix (B), of gum arabic and 1 to 50% by weight, basedon the total weight of said matrix (B), of a low molecular weightcarbohydrate or polyol.
 4. The composition of claim 3, wherein said lowmolecular weight carbohydrate is selected from the group consisting ofglucose, sucrose, maltose, lactose, 42 D.E. and 36 D.E. corn syrupsolids, erythritol, lactitol, mannitol, sorbitol, maltitol, isomalt,xylitol, hydrogenated corn syrups, hydrogenated glucose syrups,hydrogenated maltose syrups, and hydrogenated lactose syrups.
 5. Thecomposition of claim 1, wherein said matrix (B) comprises: (b) 50 to100% by weight, based on the total weight of said matrix (B), ofhydrolyzed gelatin and 0 to 50% by weight, based on the total weight ofsaid matrix (B), of a low molecular weight carbohydrate or polyol. 6.The composition of claim 5, wherein said matrix (B) comprises: (b) 50 to99% by weight, based on the total weight of said matrix (B), ofhydrolyzed gelatin and 1 to 50% by weight, based on the total weight ofsaid matrix (B), of a low molecular weight carbohydrate or polyol. 7.The composition of claim 6, wherein said low molecular weightcarbohydrate is selected from the group consisting of glucose, sucrose,maltose, lactose, 42 D.E. and 36 D.E. corn syrup solids, erythritol,lactitol, mannitol, sorbitol, maltitol, isomalt, xylitol, hydrogenatedcorn syrups, hydrogenated glucose syrups, hydrogenated maltose syrups,and hydrogenated lactose syrups.
 8. The composition of claim 1, whereinsaid matrix (B) comprises: (c) 50 to 90% by weight, based on the totalweight of said matrix (B), of a 50 to 75 Bloom gelatin and 10 to 50% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol.
 9. The composition of claim 8, whereinsaid matrix (B) comprises: (c) 60 to 80% by weight, based on the totalweight of said matrix (B), of a 50 to 75 Bloom gelatin and 20 to 40% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol.
 10. The composition of claim 9, whereinsaid low molecular weight carbohydrate is selected from the groupconsisting of glucose, sucrose, maltose, lactose, 42 D.E. and 36 D.E.corn syrup solids, erythritol, lactitol, mannitol, sorbitol, maltitol,isomalt, xylitol, hydrogenated corn syrups, hydrogenated glucose syrups,hydrogenated maltose syrups, and hydrogenated lactose syrups.
 11. Thecomposition of claim 1, wherein said matrix (B) comprises: (d) 50 to100% by weight, based on the total weight of said matrix (B), of larchgum and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol.
 12. Thecomposition of claim 11, wherein said matrix (B) comprises: (d) 50 to99% by weight, based on the total weight of said matrix (B), of larchgum and 1 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol.
 13. Thecomposition of claim 12, wherein said low molecular weight carbohydrateis selected from the group consisting of glucose, sucrose, maltose,lactose, 42 D.E. and 36 D.E. corn syrup solids, erythritol, lactitol,mannitol, sorbitol, maltitol, isomalt, xylitol, hydrogenated cornsyrups, hydrogenated glucose syrups, hydrogenated maltose syrups, andhydrogenated lactose syrups.
 14. The composition of claim 1, whereinsaid matrix (B) comprises: (e) 50 to 100% by weight, based on the totalweight of said matrix (B), of a mixture of at least two food polymersselected from the group consisting of gum arabic, hydrolyzed gelatin,gelatin, and larch gum and 0 to 50% by weight, based on the total weightof said matrix (B), of a low molecular weight carbohydrate or polyol.15. The composition of claim 14, wherein said matrix (B) comprises: (e)50 to 99% by weight, based on the total weight of said matrix (B), of amixture of at least two food polymers selected from the group consistingof gum arabic, hydrolyzed gelatin, gelatin, and larch gum and 1 to 50%by weight, based on the total weight of said matrix (B), of a lowmolecular weight carbohydrate or polyol.
 16. The composition of claim15, wherein said low molecular weight carbohydrate is selected from thegroup consisting of glucose, sucrose, maltose, lactose, 42 D.E. and 36D.E. corn syrup solids, erythritol, lactitol, mannitol, sorbitol,maltitol, xylitol, isomalt, hydrogenated corn syrups, hydrogenatedglucose syrups, hydrogenated maltose syrups, and hydrogenated lactosesyrups.
 17. The composition of claim 1, having a glass transitiontemperature of at least 35° C.
 18. The composition of claim 1 whereinsaid encapsulate is selected from the group consisting of medications,pesticides, vitamins, preservatives, and flavoring agents.
 19. Thecomposition of claim 1, wherein said encapsulate is a flavoring agent.20. The composition of claim 19, wherein said flavoring agent isselected from the group consisting of natural extracts, oleoresins,essential oils, protein hydrolysates, aqueous reaction flavors,compounded natural flavors, and artificial flavors.
 21. The compositionof claim 19, wherein said flavoring agent optionally contains aplasticizer or an emulsifier.
 22. A process for preparing anencapsulation composition, comprising: (A) an encapsulate, encapsulatedin: (B) a glassy matrix, said matrix comprising: (a) 50 to 100% byweight, based on the total weight of said matrix (B), of gum arabic and0 to 50% by weight, based on the total weight of said matrix (B), of alow molecular weight carbohydrate or polyol; or (b) 50 to 100% byweight, based on the total weight of said matrix (B), of hydrolyzedgelatin and 0 to 50% by weight, based on the total weight of said matrix(B), of a low molecular weight carbohydrate or polyol; or (c) 50 to 90%by weight, based on the total weight of said matrix (B), of a 50-75Bloom gelatin and 10 to 50% by weight, based on the total weight of saidmatrix (B), of a low molecular weight carbohydrate or polyol; or (d) 50to 100% by weight, based on the total weight of said matrix (B), oflarch gum and 0 to 50% by weight, based on the total weight of saidmatrix (B), of a low molecular weight carbohydrate or polyol; or (e) 50to 100% by weight, based on the total weight of said matrix (B), of amixture of at least two food polymers selected from the group consistingof gum arabic, hydrolyzed gelatin, gelatin, and larch gum and 0 to 50%by weight, based on the total weight of said matrix (B), of a lowmolecular weight carbohydrate or polyol, said process comprising: (i)mixing matrix (B) with a liquid plasticizer and encapsulate (A) in anextruder, to obtain a melted mixture which comprises encapsulate (A) andmatrix (B); and (ii) extruding said melted mixture, to obtain anextruded mixture.
 23. The process of claim 22, wherein said liquidplasticizer is selected from the group consisting of water; glycerol;propylene glycol; aqueous solutions of glycerol, propylene glycol,monosaccharides, and disaccharides; and invert and high fructose cornsyrups.
 24. The process of claim 22, wherein said liquid plasticizer iswater.
 25. The process of claim 22, further comprising cooling saidextruded mixture.
 26. The process of claim 22, wherein said encapsulateis selected from the group consisting of medications, pesticides,vitamins, preservatives, and flavoring agents.
 27. The process of claim22, wherein said encapsulate is a flavoring agent.
 28. The process ofclaim 27, wherein said flavoring agent is selected from the groupconsisting of natural extracts, oleoresins, essential oils, proteinhydrolysates, aqueous reaction flavors, compounded natural flavors, andartificial flavors.
 29. The process of claim 27, wherein said flavoringagent comprises a plasticizer or an emulsifier.
 30. The process of claim22, wherein said extruder is a twin screw extruder.
 31. An encapsulationcomposition, comprising: (A) an encapsulate, encapsulated in: (B) aglassy matrix, said matrix comprising: (a) 50 to 100% by weight, basedon the total weight of said matrix (B), of gum arabic and 0 to 50% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol; or (b) 50 to 100% by weight, based on thetotal weight of said matrix (B), of hydrolyzed gelatin and 0 to 50% byweight, based on the total weight of said matrix (B), of a low molecularweight carbohydrate or polyol; or (c) 50 to 90% by weight, based on thetotal weight of said matrix (B), of a 50-75 Bloom gelatin and 10 to 50%by weight, based on the total weight of said matrix (B), of a lowmolecular weight carbohydrate or polyol; or (d) 50 to 100% by weight,based on the total weight of said matrix (B), of larch gum and 0 to 50%by weight, based on the total weight of said matrix (B), of a lowmolecular weight carbohydrate or polyol; or (e) 50 to 100% by weight,based on the total weight of said matrix (B), of a mixture of at leasttwo food polymers selected from the group consisting of gum arabic,hydrolyzed gelatin, gelatin, and larch gum and 0 to 50% by weight, basedon the total weight of said matrix (B), of a low molecular weightcarbohydrate or polyol, wherein said composition is prepared by aprocess comprising: (i) mixing matrix (B) with a liquid plasticizer andencapsulate (A) in an extruder, to obtain a melted mixture whichcomprises encapsulate (A) and matrix (B); and (ii) extruding said meltedmixture, to obtain an extruded mixture.
 32. The process of claim 31,wherein said liquid plasticizer is selected from the group consisting ofwater; glycerol; propylene glycol; aqueous solutions of glycerol,propylene glycol, monosaccharides, and disaccharides; and invert andhigh fructose corn syrups.
 33. The process of claim 31, wherein saidliquid plasticizer is water.
 34. The process of claim 31, furthercomprising cooling said extruded mixture.
 35. The process of claim 31,wherein said encapsulate is selected from the group consisting ofmedications, pesticides, vitamins, preservatives, and flavoring agents.36. The process of claim 31, wherein said encapsulate is a flavoringagent.
 37. The process of claim 35, wherein said flavoring agent isselected from the group consisting of natural extracts, oleoresins,essential oils, protein hydrolysates, aqueous reaction flavors,compounded natural flavors, and artificial flavors.
 38. The process ofclaim 35, wherein said flavoring agent comprises a plasticizer or anemulsifier.
 39. The process of claim 31, wherein said extruder is a twinscrew extruder.